Patent · US Expired

Image forming apparatus

US4939548A · kind A · utility

25Cited by
1References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 29, 1989
Grant dateJul 3, 1990
Priority date
Expiry dateMar 29, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/018
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In an image forming apparatus, a support member attachably and detachably supporting a plurality of developing units is provided for moving the developing units upwardly and downwardly or along a common circular orbit by vertical or rotative movement. A vertical movement support member balances with balancers, while a rotary support member has rotative balance by mutual position of each developing unit. A lock member for locking a support member at a desired position and a sensor for detecting the movement of the support member when unlocked are actuated for judging an unbalanced state of the support member by a detecting signal of the sensor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.